Emergency electric lighting installations

ABSTRACT

A portable handlamp incorporating a rechargeable battery is removably mounted in a bracket to form an emergency electric lighting installation. It incorporates a transformer and rectifier arranged to trickle charge the battery from a supply, and the transformer acts on an armature secured to a bolt to lock the lamp in the bracket so long as the supply is maintained, but to switch on the light and release the lock if the supply fails.

United States Patent {72] lnventor John Scott Netherwood BarkerSouthampton, England [21] Appl. No 765,193 [22] Filed 01.1.4, 1968 [45]Patented July 6, 1971 [73] Assignee Bardic Systems Limited Northam,Southampton, England [32} Priority Oct. 5, 1967 [33] Great Britain [31]45,601/67 [54] EMERGENCY ELECTRIC LIGHTING ZNSTALLATIONS 3 Claims, 4Drawing Figs.

{52] U.S.Cl 240/37.1, 240/106, 315/86 [51] 1nt.Cl F21v 9/04 {50] Fieldof Search 240/37. 1,

[56] References Cited UNlTED STATES PATENTS 2,863,038 12/1958 Lombardo240/37.1 3,217,156 11/1965 Sherwood 240/106 3,233,091 2/1966 Hunt240/37.1 X

Primary Examiner-Samuel S. Matthews Assistant Examiner-Richard L. MosesAltomey-watson, Cole, Grindle and Watson ABSTRACT: A portable handlarnpincorporating a rechargeable battery is removably mounted in a bracketto form an emergency electric lighting installation. It incorporates atransformer and rectifier arranged to trickle charge the battery from asupply, and the transformer acts on an armature secured to a bolt tolock the lamp in the bracket so long as the supply is maintained, but toswitch on the light and release the look if the supply fails.

This invention relates to emergency electric lighting installations ofthe type including supply terminals, a rechargeable battery, a lamp,means for connecting the battery so as normally to be trickle chargedfrom the supply terminals, and means responsive to failure of the supplyfor automatically connecting the lamp to the battery to provide anemergency lighting unit.

According to the present invention the installation comprises a fixedportion or racket including the supply terminals and a portable portionor handlamp including the battery and the lamp, which is readilydetachable from the fixed portion to form a portable lighting unit, butis locked to the fixed portion by locking means responsive to failure ofthe supply so as to release the portable handlamp, as well asilluminating the lamp, if the supply fails.

The means for recharging the battery preferably include a transformerwhich also functions as a solenoid to keep the locking means engagedwhile the supply is maintained.

In one form of the invention, in which the transformer is carried by thehandlamp, the transformer functions as a relay to actuate contacts toilluminate the lamp.

The arrangement has the advantage that the handlamp cannot be removedfrom'its racket during normal conditions and hence is always availablein emergency if the supply should fail, and can then be withdrawn fromits racket and used wherever it may be needed.

The invention may be put into practice in various ways but one specificembodiment will be described by way of example with reference to theaccompanying drawings in which:

FIG. 1 is a circuit diagram; I

FIG. 2 is a somewhat diagrammatic side elevation, partly in section;

FIG. 3 is a front elevation of an emergency electric lightinginstallation embodying the invention, and

FIG. 4 a rear elevation of the handlamp.

The installation comprises a fixed portion or bracket and aportable'portion or handlamp 20. The bracket is'arranged to be securedto a bench or wall and comprises a bottom 11, a back 12 and triangularsidewalls 13.

The handlamp comprises a cast casing 21 with a removable bottom 22 thesides 23 of which project slightly beyond the casing and are receivedunder a pair of horizontal ribs 14 on the sidewalls of the bracket. Thusthe handlamp can slide horizontally into the bracket in what will bereferred to as a rearward direction. The handlamp has at the back a plug24 to cooperate with a socket carried by the bracket and connected tosupply mains. The bottom of the handlamp is secured to the casing by apair of hooked wire clips 25 each pivoted to a slide 26 which can bedrawn up by a screw 27 and nut 28 to hold the bottom firmly.

At the front the handlamp has a lamp 30 in a holder 31 fitted with areflector 32, and along the top a carrying handle 33. Within the body ofthe handlamp is a nickel-cadmium battery 34 and a combined transformer,relay and lock 35. The transformer has a primary winding 36 connected tothe plug 24, and a secondary winding 37 connected through a halfwaverectifier 38 and a resistor 39 to the battery 34 to tricklecharge it. Inaddition the transformer core acts on a relay armature 40 carrying acontact 41 cooperating with a contact 42 to connect the lamp across thebattery, the armature 40 also acting on a locking bolt 45. Thus thearmature 40 by carried by the bolt 45 which is mounted to slide in aguide sleeve 46 upstanding from, and formed integraly with, the bottom22. A

helical spring 47 urges the bolt upwards. The contact 41 is formed bythe armature itself whilst the contact 42 is formed by the lower end ofa rod 48 mounted to slide in the lamp holder 31 and urged upwards by aspring 49 acting on a collar secured to it. The upper end of the rod 48extends through a hole in the top of the casing and forms a button 50.Thus in normal operation the transformer is energized and pulls thearmature 40 down (against the action of the spring 47) to a lowerposition shown in full lines in FIG. 2 in which the contacts 41 and 42are separated and the lower end 51 of the bolt 45 projects through ahole 52 in the bottom 11 of the bracket to lock the handlamp inposition. The hole 52 is masked by a domed cover 53 to prevent access tothe lower end 51 of the bolt to release it. When the transformer isdeenergized the spring 47 raises the armature to the position shown inchain lines, in which the contacts 41 and 42 are in engagement. Inaddition if the transformer is energized and the armature is in itslower full-line position, the button 50 can be pressed to lower the rod48 and bring the contact 42 into engagement with the contact 41 fortesting purposes.

Thus so long as the supply 3 maintained the transformer is energized andthe armature acts on the bolt 45 to cause it to project through thebottom of the handlamp, and through the hole 52 in the bracket, therebypreventing the handlamp from being drawn forward from the bracket. Thecontacts 41 and 42 remain open to disconnect the lamp from the battery,and the battery receives a slow trickle charge.

In the event of the supply failing, the transformer is deenergized andthe locking bolt is withdrawn by the spring 47 so that the handlamp canbe withdrawn from the bracket for use wherever it is required. At thesame time, the armature causes the contacts 41 and 42 to close, wherebythe lamp is automatically illuminated, whether the lamp is withdrawn orleft in place in the bracket.

On the supply being restored and the lamp being returned to the bracket,or if the lamp has already been returned to the bracket, the transformerwill be reenergized to open the lamp contacts 41 and 42 and relock thehandlamp in position.

Thus during normal conditions the handlamp remains locked to the bracketso that it cannot be removed or disconnected from the trickle-chargingcircuit, and it will thus always be available in its place and fullycharged when required in an emergency.

What Iclaim as my invention and desire to secure by Letters Patent is:

1. An emergency electric lighting installation of the type in-.

cluding supply terminals, a rechargeable battery, a lamp, means forconnecting the battery so as normally to be trickle charged from thesupply terminals and means responsive to failure of the supply forautomatically connecting said lamp to said battery to provideanemergency lighting unit, in which the installation comprises a fixedbracket including said supply terminals and a handlamp including saidbattery and said lamp, which is readily detachable from said fixedbracket to form a portable lighting unit, and locking means responsiveto failure of the supply for locking said headlamp to said fixed bracketand for releasing said portable handlamp, as well as illuminating saidlamp, if the supply fails.

2. An emergency electric lighting installation as claimed in claim 1 inwhich means for recharging battery include a. transformer which alsofunctions as a solenoid to keep said locking means engaged while thesupply is maintained.

3. An emergency electric lighting installation as claimed in claim 2 inwhich said transformer is carried by said handlamp, and said transformerfunctions as a relay to actuate contacts to illuminate said lamp.

1. An emergency electric lighting installation of the type includingsupply terminals, a rechargeable battery, a lamp, means for connectingthe battery so as normally to be trickle charged from the supplyterminals and means responsive to failure of the supply forautomatically connecting said lamp to said battery to provide anemergency lighting unit, in which the installation comprises a fixedbracket including said supply terminals and a handlamp including saidbattery and said lamp, which is readily detachable from said fixedbracket to form a portable lighting unit, and locking means responsiveto failure of the supply for locking said headlamp to said fixed bracketand for releasing said portable handlamp, as well as illuminating saidlamp, if the supply fails.
 2. An emergency electric lightinginstallation as claimed in claim 1 in which meAns for recharging batteryinclude a transformer which also functions as a solenoid to keep saidlocking means engaged while the supply is maintained.
 3. An emergencyelectric lighting installation as claimed in claim 2 in which saidtransformer is carried by said handlamp, and said transformer functionsas a relay to actuate contacts to illuminate said lamp.